Sharpening device



June 11, 1940. c. R. ELLIS SHARPENING DEVICE Filed April 29. 1939 2Sheets-Sheet 1 I'll INS/ENTER. ELLIE HTTUE'NEE June 11, 1940.

c. a. ELLIS SHARPENING DEVICE Filed April 29, 1939 2 Sheets-Sheet 2INYENTUR.

[1 R- ELLIS Btrr \-m-w HTTURNEH.

Patented June 11, 1940 rarer DFFlCE SHARPENING DEVICE OlarenceRayrnondEllis, Sausalito, Calif.

. ApplicationAprilZB, 1939, Serial No. 270,857

3 2 Claims.

This invention relates to improvements in sharpening devices and hasparticular reference to a device for sharpening screwdrivers, and moreCir in the bottom of the screwhead slot.

Acfurther object of this invention is to produce a device of thischaracter which is simple to operate, economical to manufacture and onewhich will accommodate screwdrivers of various sizes and yet produce auniformresult, irrespective of the sizeof the screwdriver.

Afurther object isto provide means for limit ing the end grindingactionwhen facing the end of thescrewdriver after the sharpeningopera- 1) tion.

. during the course of the following description. ,In the accompanyingdrawings forming a part of this specification and in which like numerals5 are employedto designate like parts through the same,

Fig. 1 is a side elevation of my device.

i Fig. 2 is an end elevation looking from the left of Fig. 1.

Fig. 3 is a side elevation showing portion thereof broken away in orderto illustrate the mechanism. l

Fig. 4 is a top plan view of Fig. 2.

Fig. 5 is an enlarged fragmentarydetailed view,

5 showing the sharpening operation.

Fig. 6 is. an enlarged fragmentary detailed view, showing the endgrinding operation and Fig. ,lis. a fragmentary detailed view, showingthe rear arrangement.

Screwdrivers rapidly become bent, burred,

chipped and otherwise. deformed. It is therefore necessary to resharpenthe bit, in order to have. it properly function, and without marring thehead of the screw uponwhich it is used.

Applicant has devised a sharpening device which will grind the oppositesides of the bit evenly with relation to the axis of thescrewdriver,which is very important, particularly when l dealing with minute screwssuch as are used in a 501 jewelers trade; and applicant has furtherprovided a device wherein the end of the screwdriver, after beingsharpened, is round, square or, in other words, faced, so that it willproperly seat in the slot of the screw. 55 In the accompanying drawingswherein for Other objects andadvantages will be apparent the purposeofillustration is shown a preferred embodiment ofmy invention, it will benoted that my device consists of a base 5, which is preferablyrectangular in shape and forms a convenient means for mounting my devicein a vice commonly used on jewelers benches. Upon this base is secured arectangular housing 6, the front of which is open, as shown inFig. 2..Slidably mounted in the housing 6 is a carrier 1, which carrier ispressed upwardly by a spring 3, inter 10 posed between the bottom ofthehousing 6 and the bottom of the carrier 1. Counteracting the tension ofa spring 8 is a threaded member 9, having a knurled head ll, through themedium of which the screw member 9 may be adjustably 15 rotated tomovethecarrier l against the tension of the spring 8. l

Mounted in the carrier 1 is a shaft [2, upon whichis secureda drivinggear l3 and a grinding wheel M. A shaft I6 is journalled in the housing2 6 and passes through slots formed-inthe carrier 'l, and has mountedthereon a gear H, which meshes with the gear l3. The shaft alsocarries.agrinding wheel Hi. This shaft'may be driven in any convenient manner,but I have here shown 5 a crank handle [9 rotating the same. l

Secured to the front of the housing 6 is an extension 2|, which servesto position the bifurcated end of a tool carrier 22. The carrier 22comprises a fiat base portion 220. having one end 30 remov-ably pivotedtothe housing at 2|. From each side edge of the flat base portionextends a side portion 22b, these side portions being parallel. Theupper end of this tool carrier extends through a slot 23, formed in thetop of the 5 housing fi.

Mounted in the carrier is a tool holder 24, in which is formed bores 26,2?, 28 and 29. This tool holder is mounted upon stub shafts 3|, whichride in inclined slots 32, formed on the opposite 0 sides of thetoolcarrier. The tool holder is in theform of a block having parallelside faces and fits snugly between the sides 22b of the carrier.Moreover, the block forming the tool holder has a square periphery andthe stubshafts or pins 3| 45 are fixed in the block in the centers ofits side faces so that the block may he slid outwardly and inwardly toand from the carrier base 22a. and when slid outwardly it maybe rotated.By this means aselected peripheral side of the block may be engagedagainst the base 22a. The base 22a is provided with an opening 220 andwhen a selected side of thetool holder engages the base a respectivebore will align with the hole or opening 220. The several bores are ofdifferent diameters to accommodate different diameters I which serves toprevent grooving of the stone.

of screwdrivers and by the means just described, a selected bore may bealigned with the opening Zlic for the reception of the screwdriver to bepresented. This arrangement permits the tool holder to be moved awayfrom the grinding wheels, so as to be rotated, as indicated in dottedlines in Fig. 1, the purpose of which will be later seen.

It is also to be noted here that the edge faces of the tool holder areeach provided with an inclined groove 33, the purpose ofwhich will belater seen.

The tool carrier is provided with a slot 1%, as best illustrated inFigs. 5 and 6, the slot being of sufiicient horizontal width toaccommodate the widest screwdriver which may be sharpened in the device.The slot is formed by striking the metal so as to form curved lips 35,separated from each other a predetermined distance, the purpose of whichwill be later seen.

The operation of my device is as follows: 7

Assuming that the parts have been assembled, as shown in Figs. 1 and 2,and it is desired to sharpen a screwdriver, the same is placed throughone of the bores, as, for instance, the bore 26,

and assuming the same is the proper size to accommodate the particularscrewdriver to be sharpened. When the screwdriver is in place, as shownin Fig. 5, the point thereof will come to rest between the grindingwheels it and it.

The operator now presses thethurnb against the thumb piece A of thescrewdriver, and the first finger is placed at approximately the point Bon top of the tool holder. The crank L9 is now rotated in a clockwisedirection, while the first finger moves the carrier back and forth, asindicated by the double ended arrow of Fig. 2, thus moving thescrewdriver bit back and forth across the stone during the sharpeningoperation,

After the bit has been ground a sufiicient amount, the tool as a wholeis removed from. the holder and laid in the groove 33 on the'top of 1'the holder, as illustrated in Fig. 6, with the point engagement with thewheel [8. By again rotating the crank IS the end of the bit will beground away until the distance between the curved lips 36 preventfurther movement of the bit toward the grinding wheel.

It is, of course, understood that the tool carrier is moved back andforth in the same manner to causethe bit to travel across the full faceof the grinding wheel, as previously described for the sharpeningoperation.

It will thus be seen that I have produced a one side, a pair of adjacentgrinding wheels mounted in said housing with their axes parallel toeaohother and equidistant from the open side thereof a tool carrierincluding a flat base portion having an opening therein and a pair ofparallel side plates, said side plates having oppositely disposed slotsextending outwardly from the centers of the plates, a tool holder havingparallel sides and a square periphery and slidably and rotatably fittedbetween said side plates to .have its peripheral sides selectivelyengageable against the carrier base portion, said holder being providedwith tool positioning means for each side of the holder peripheryalining with the base opening upon a selected side of the tool holderengaging said base portion, and pivot pins fixed in said tool holder atthe center of its'sides and engaging in said slots.

2. The sharpening device of claim 1 wherein the carrier has one endpivoted to the housing to permit swinging of the tool holdertransversely of the grinding Wheels.

CLARENCE RAYMOND ELLIS.

